With the advancement of technology, the number of transistors on per unit area of an electronic element is constantly increased to produce a largely increased amount of heat when the electronic element operates. Also, the operating frequency of the electronic element is higher and higher. Switching on/off of the transistors in operation generates heat as well, which also forms one reason why the electronic elements generate more heat than ever before. The produced heat must be quickly removed from the electronic element, or the heat can lower the computation speed of chips. In a worse condition, the heat can adversely affect the service life of the chips. To improve the heat dissipation efficiency of the electronic element, heat radiation fins of a heat sink are used to dissipate the heat from the electronic elements into the ambient air through natural or forced convection.
A heat pipe has a very small cross sectional area but it enables transfer of a large amount of heat from a point to another distant point for dissipation even though there is only a small temperature difference between the two points, and its operation does not need an applied power supply. With these advantages, heat pipes have been widely used in various heat-producing electronic products as one of the widely adopted heat transfer elements.
A currently very popular way of heat dissipation is to mount a heat dissipation device, such as a heat sink, especially a heat sink with heat pipes, to a heat-generating element. The heat sink is made of a material having high heat conductivity. Also, with the help of a working fluid and a wick structure provided in the heat pipe, the heat sink not only provides high heat transfer ability, but also has advantageous light weight to reduce the overall weight, production cost, and system complexity caused by the heat dissipation device.
A conventional heat sink with heat pipe includes a plurality of heat radiation fins and at least one heat pipe. Each of the heat radiation fins has at least one through hole formed thereon for the heat pipe to extend through, such that the heat pipe is connected to the heat radiation fins. However, the conventional heat pipe usually has a round or an oval cross section, which provides only a point-to-point contact and accordingly, a very small contact area between the heat pipe and the heat radiation fins, resulting in slow and poor heat transfer effect of the heat sink.
In conclusion, the prior art heat dissipation device has the following disadvantages: (1) having low heat transfer effect; and (2) having poor heat dissipation efficiency.
It is therefore tried by the inventor to develop an improved heat dissipation device to overcome the drawbacks and problems in the conventional heat dissipation device.